An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 m. Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth âs surface. They are among the flattest, smoothest and least explored regions on Earth.
Jim Beckwourth. On this day in 1844, Jim Beckwourth discovered a path through the Sierra Nevada Mountains that now bear his name. Beckwourth Pass on U.S. Alt 40 between Reno, Nevada and Sacramento, California made overland travel to the gold fields of California. Tweet.
- James Marshall, 1848. At a time when restless Americans were already itching to go west, the discovery of gold in California in 1848 was like gasoline on a fire. Within a year of its discovery, emigrants using the California Trail were flooding into the Sierra Nevada Range by the thousands. John Sutter was a Swiss immigrant who came to California in 1839 with a dream of building an agricultural empire.